Night Shifts, Broken Sleep, and an Old Idea Making a Comeback

By Dr Fiona Graham

In July I was invited to join Sonia on the BBC Essex Breakfast Show (22 July, 07.39 to 07.44, still up on BBC Sounds) to talk about something we see often at Chelmsford Private GPs: sleep in night shift workers. If you've ever worked nights, you'll know the kind of tiredness it brings, not just “I need a nap” tired, but a deeper, and sometimes, much harder to shift exhaustion. We talked about why that happens, what it means for your health, and an idea doing the rounds in sleep science: that splitting sleep into two chunks might suit some shift workers better than chasing one long block. Here's the fuller story.

Why night shifts take such a toll

We are all built around a roughly 24 hour internal clock that quietly runs the show, nudging us toward alertness or sleepiness, raising and lowering hormones like cortisol and melatonin, shifting our body temperature up and down. Night shift work means asking your body to be sharp and switched on exactly when that clock wants you asleep, then asking it to sleep when the clock wants you awake. If you do that for months or years, and quite understandably, it takes a toll.

The evidence here is well established. Long term night and rotating shift work has been linked to a higher risk of metabolic problems and disturbed blood sugar regulation, cardiovascular disease, weight gain, and low mood, along with more workplace accidents and safety incidents. None of this means every shift worker is destined for poor health, but these risks deserve real attention, not a shrug and a strong coffee.

The “one long sleep” myth

Most conventional advice tells shift workers to aim for a single, unbroken 7 to 9 hour sleep during the day, just as you would at night. That's often close to impossible. Daylight, noise, family life, and your own body clock all work against it. Many shift workers sleep for a few hours, wake up naturally, and then can't drop off again, only to feel like they've somehow failed at rest. It's a familiar, frustrating cycle. And it's exactly where things get interesting.

An old pattern, rediscovered

Roger Ekirch, a historian at Virginia Tech, spent years combing through diaries, court records and old medical texts and kept finding the same thing: references to a “first sleep” and a “second sleep,” separated by an hour or so of quiet wakefulness in the middle of the night. People would go to bed, wake naturally after midnight to potter, pray or simply lie and think, then drift into a second sleep before dawn. He's since catalogued well over a thousand historical references to this pattern, and his work has shaped how scientists think about waking in the small hours, suggesting it may not always be a disorder, but an echo of a sleep pattern that was entirely normal before artificial light stretched our days. It's a lovely idea, though not without its critics: some historians have pushed back on how widespread this pattern really was, and Ekirch has had to defend his reading of the evidence.

Where Norway comes in

This bit of history connects to something happening right now. Dr Line Moen, an occupational health researcher at Norway's National Institute of Occupational Health in Oslo, has been studying shift workers above the Arctic Circle, where the sun barely sets in summer. Using wearable sleep trackers, her team noticed many shift workers weren't collapsing into one long sleep after a night shift at all; they were naturally sleeping in two distinct blocks, waking partway through the day before a second sleep later on. Moen is now working through the wider scientific literature on biphasic sleep in shift workers with the hope that this research may eventually turn into clear, practical guidance for shift workers, with fuller results expected later this year.

How things stand currently

We're not at the point where anyone can confidently tell shift workers to deliberately split their sleep. What we can say is that if you naturally wake partway through your daytime sleep and then manage a second sleep or a good nap afterwards, that may be a completely normal pattern rather than a sign you're doing something wrong. Try not to feel anxious about it, and watch this space, because clearer guidance may well be on its way.

A gentler, lifestyle medicine approach

While the research catches up, there's plenty you can do now. Here at Chelmsford Private GPs we like to think about this holistically, with light, food, movement, substances and stress all working together.

Get the light right. Light is the single biggest lever for your body clock. Wear sunglasses on the way home to soften morning light and make your bedroom dark with blackout curtains or an eye mask. Bright light early in your shift can help to keep you alert.

Give yourself a proper wind down. Even in daylight, a short routine before sleep, such as a shower, some gentle stretching, or dimming your screens, signals to your body that rest is coming.

Nap with intention. A planned 20 to 90 minute nap before a night shift can genuinely lift alertness and safety, especially during the toughest early hours stretch.

Be mindful with caffeine. Lovely early in a shift, best avoided in the final few hours before you plan to sleep, since its effects can linger far longer than we think.

Be kind to yourself about alcohol. This came up directly on air, and it's worth saying plainly: alcohol might feel like it helps you drop off, but it fragments your sleep and robs you of the deep, restorative stages you need most. For anyone already fighting their body clock, it tends to make things worse, not better. A dark, quiet room and a proper wind down will serve you far better than a nightcap.

Think about meal timing. Heavy meals in the small hours ask a lot of a digestive system that's also on the “wrong” schedule. Where you can, keep your biggest meal earlier in the shift and go lighter overnight.

Keep moving. Regular exercise supports your circadian rhythm, mood and metabolic health, all areas shift work puts under pressure. Even a little, consistently, goes a long way.

Check in on your mental health. Working while everyone else sleeps can be isolating, and combined with disrupted sleep it's a real risk factor for low mood and anxiety. Staying connected to the people who matter to you, and being honest with yourself or your GP if you're struggling, is just as important as anything physical. It's a conversation we have regularly with shift working patients at Chelmsford Private GPs, and one worth having sooner rather than later.

The takeaway

Night shift work carries real health risks, and they're worth taking seriously. But some of what feels like “bad” sleep, waking naturally partway through your rest, may not be a failure at all, but a very old, very human pattern that researchers like Line Moen are now studying properly. Until firmer guidance arrives, the kindest thing you can do for yourself is the practical thing: manage your light, protect your wind down, nap wisely, go easy on caffeine and alcohol, eat sensibly, keep moving, and ask for support when you need it. Good sleep hygiene, adapted thoughtfully to shift work, remains our best and most reliable tool.

You can hear the original conversation on BBC Sounds: BBC Essex Breakfast Show with Sonia, 22 July, 07.39 to 07.44.